Magic texture with emission
I think you want to go to the node editor and plug the texture into the color of the emission shader of your material. 

You can control the strength of the emission shader in the node editor. 

If you want the emission shader to light other objects, in Eevee the emission shader doesn't light other objects unless you add an irradiance volume (shift + A -> Light probe -> irradiance volume) and wrap the scene you want with it and then bake the indirect lighting in the render tab.